The present invention relates to a new and improved construction of controlled deflection roll of the type comprising a stationary roll support or core and a substantially tubular-shaped roll shell rotatable about such stationary roll support.
In particular, the controlled deflection roll of the present invention--also sometimes referred to in the art as rolls with bending or sag compensation--has the ends of the tubular-shaped roll shell rotatably mounted at the stationary roll support or core. At least one hydrostatic support or pressure element is arranged between the stationary roll support and the roll shell, this hydrostatic support element being guided at the roll support and having a contact surface upon which slidingly bears the inner surface of the roll shell. Between the roll support and the support element there is arranged a hydraulic pressure chamber connected with a suitable source of hydraulic pressurized fluid medium. The contact surface of the hydrostatic support element is provided with a number of hydrostatic bearing pockets which are connected by means of throttle channels with the pressure chamber.
A controlled deflection roll of this type is known to the art, for instance from U.S. Pat. No. 3,802,044, granted Apr. 9, 1974. With this state-of-the-art controlled deflection roll the hydrostatic support or pressure elements are configured as pistons or plungers, wherein the pressure chamber is in the form of a cylinder which is formed either at the roll support, or, in the event that the pressure or support element has the configuration of a plunger, then at the latter itself. Controlled deflection rolls constructed in this manner permit large strokes or displacement movements of the pressure or support elements, so that there can be attained large bending-through or deflection of the roll support and large contact forces. When the cylinder bores are formed at the roll support or core, then such constitute a weakening of such roll support. Cylinder chambers formed at the pressure or support elements equally cause weakening of the roll support, since its cross- sectional area must be selected to be correspondingly smaller to provide space for the pressure or support elements.
On the other hand, there are certain fields of application where the controlled deflection roll does not require any large displacement movement or stroke of the pressure or support elements, but at the same time, however, the roll support must be rigid as possible and also inexpensive.